1. Field of the Invention
The present invention relates to a light source unit capable of shining light of high in-plane uniformity, an illuminating method of this light source unit, and a projector including the light source unit.
2. Description of the Related Art
In these days, data projectors are used on many occasions as an image projection unit which projects images including an image of a screen and a video image of a personal computer, as well as images based on image data which is stored on a memory card on to a screen. In these data projectors, light emitted from a light source converges at a micromirror display element called a DMD (Digital Micromirror Device) or a liquid crystal panel so that a color image is displayed on a screen.
Conventionally, the mainstream of these projectors has been those which utilize a high-intensity discharge lamp as a light source. In recent years, however, there have been made various developments on projectors which use, as a light source, a light emitting diode, a laser diode, an organic EL device, a luminescent material or the like.
Additionally, in recent years, there have also been made various proposals of light source units having a light emitting diode as an excitation light source and a luminescent wheel in which a luminescent material layer which converts ultraviolet light emitted from the excitation light source as excitation light into visible light is formed on a transparent base.
In the present situations in which the production of a light emitting diode is difficult which can emit highly bright light of a range of green wavelengths as a light source for the projectors described above, Japanese Unexamined Patent Publication No. 2011-53323 discloses a projector which utilizes a light source unit which emits highly bright light of a range of green wavelengths by using a green light emitting luminescent material and a small and high-output laser diode as an excitation light source. As a result, the projector can project a clear image on a screen even in a bright room.